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An Overview of the
Fabrication of Ultraclean Film™
There is a vast distinction between Ultraclean Film™ and commercially clean
film that is important to note. The development of Ultraclean Film™, which is
used for the most critical products, begins with the resin at our extrusion
plants.
Ultra Cleanliness Starts At the Beginning of the Manufacturing
Process
In developing Ultraclean Films™, particular care must be taken to remove
impurities from the resin and to control factors such as air cleanliness and
its moisture vapor content. Various controls must be used during the
extrusion process to render an "ultra" clean product.
After extrusion has been completed, the film must be carefully handled and
stored to prevent gross contamination. KNF Clean Room Products imposes the
most exacting quality-control standards on its resin suppliers, and
continually monitors the fabrication processes, as well as any handling and
storage of the film.
The final cleaning of film takes place in our clean room facility under the
most scrupulous conditions currently attainable in the contamination control
field. Here, we achieve critical control of temperature, humidity, and the
level of dust particles. Our machinery has been designed to both clean the
film and eliminate any particles or contaminants during processing. Fluids
used during testing are filtered to levels 5 to 10 times greater than the
ultimate test requirements for clean film.
Contamination Free Storage and Routine Testing
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After cleaning, the film is maintained in a totally
dust-free environment and inspected for compliance with the cleanliness
levels stipulated by the customers and/or end-users. It is then packaged in
double- or triple-barrier bags and certified by Quality Assurance
representatives as to its compliance with standards.
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Testing is an essential part of the cleaning process,
and is performed on a regular basis.
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TABLE l: PRECISION PACKAGING MATERIALS—SURFACE CLEANLINESS REQUIREMENTS:
Clean Room Products and MSC-C-25 SPECIFICATIONS
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Level
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Particulate Distribution Per Sq. Ft. of Surface Tested
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Nonvolatile Residue Per Sq. Ft. of Surface Tested
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1
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0-5
microns
5-15 "
15-25 "
25-50 "
-50 "
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Unlimited
40
20
6
02
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1
mg.
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2
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0-5
microns
5-15 "
15-25 "
20-50 "
50-100 "
-100 "
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Unlimited
50
25
10
5
02
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1
mg.
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3
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0-10
microns
10-25 "
25-50 "
50-100 "
100-175 "
-175 "
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Unlimited
300
50
10
5
02
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1
mg.
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TABLE II: SURFACE CLEANLINESS LEVELS, KSC-C-123F PRECISION
PARTICULATE LEVELS
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Level
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Particle Size, Range Microns
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Max. No. of Particles, Per Ft
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Level
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Max. Qty. NVR MG Per Ft
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25
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<5
5 to 15
>15 to 25
>25
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Unlimited
19
4
0
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A
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1.0
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50
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<15
15 to 25
>25 to 50
>50
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Unlimited
17
8
0
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B
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2.0
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100
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<25
25 to 50
>50 to 100
>100
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Unlimited
68
11
0
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C
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3.0
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150
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<50
50 to 100
>100 to 150
>150
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Unlimited
47
5
0
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D
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4.0
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200
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<50
50 to 100
>100 to 200
>200
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Unlimited
154
16
0
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E
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5.0
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Additional higher particle levels per the specifications are not shown
here, but are available upon request.
Notes:
1. Unlimited means that particles in this range are not counted; however, any
obscuring of the filter grid lines shall be cause for rejection.
2. Zero particles shall mean less than 1 particle on the average, per square
foot.
Testing At Your Facility
Tests performed by customers at their facilities are also vital in
verifying and maintaining cleanliness levels. To assist in this regard, we
have developed a standard test program for your use, which has been accepted
by prime facilities throughout the U.S. "Procedure For Determination of
Particle Counts in Clean Film Packaging" is available in document-form
upon your request, at no charge.
Specifications
Clean Room Products has established levels of surface cleanliness of
Ultraclean Film™ , which are fast becoming the recognized standards of the
industry. Our levels correspond to the Johnson and Marshall Space Flight
Center specifications, as well as those of the Kennedy Space Flight Center.
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